The Total Number of Galaxies in a Rich, Regular Cluster

question 133

Multiple Choice

The total number of galaxies in a rich, regular cluster of galaxies such as the Coma cluster is believed to be

• A) between a few thousand and 10,000.
• B) over 1 million.
• C) about 1000.
• D) several dozen.

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Definitions:

Epinephrine

Adrenaline, a dual-function substance acting as both hormone and neurotransmitter, is key in initiating the body's fight-or-flight response.

Serotonin

A neurotransmitter involved in regulating mood, appetite, sleep, and other functions, often associated with feelings of well-being and happiness.

Dopamine

A neurotransmitter in the brain associated with pleasure, movement, and reward-motivated behaviors.

B Lymphocytes

A type of white blood cell that plays a significant role in the immune system by producing antibodies to combat infections.